As a new type of light source, light emitting diode (LED) lamps have shown their wide range of applications due to the features such as energy saving, high efficiency and low cost, etc. In more and more applications, users prefer to use LED lamps to replace the traditional fluorescent lamps.
Since the LED lamps is driven by the direct current, and need a stable current to ensure its serving life. While the current LED lamps are generally connected to a mains power supply, when the power is turned on and off, it is prone to occur the voltage and current fluctuations. Such fluctuations may affect the luminous stability and the service life. Thus, it is necessary to design stable LED lamps.